add numerical recipes library

2025-09-12 18:55:25 +09:00
parent d4dff245bd
commit 2c75620ec9
1344 changed files with 63869 additions and 0 deletions
--- a/lib/nr/cpp/recipes/ftest.cpp
+++ b/lib/nr/cpp/recipes/ftest.cpp
@@ -0,0 +1,22 @@
+#include "nr.h"
+
+void NR::ftest(Vec_I_DP &data1, Vec_I_DP &data2, DP &f, DP &prob)
+{
+	DP var1,var2,ave1,ave2,df1,df2;
+
+	int n1=data1.size();
+	int n2=data2.size();
+	avevar(data1,ave1,var1);
+	avevar(data2,ave2,var2);
+	if (var1 > var2) {
+		f=var1/var2;
+		df1=n1-1;
+		df2=n2-1;
+	} else {
+		f=var2/var1;
+		df1=n2-1;
+		df2=n1-1;
+	}
+	prob = 2.0*betai(0.5*df2,0.5*df1,df2/(df2+df1*f));
+	if (prob > 1.0) prob=2.0-prob;
+}